Estimation of DNA repair synthesis in peripheral blood lymphocytes from asthmatic patients treated with oral corticosteroids

Introduction: Oral corticosteroids (OCSs) are used in the long term management of severe asthma, and the evaluation of effects of these medecines on DNA repair synthesis seems to be important. Aim: To investigate the intensity of the DNA repair synthesis in asthmatic patients treated with OCSs. Methods: The levels of spontaneous and UV-induced unscheduled DNA synthesis (UDS) in peripheral lymphocytes were evaluated for 58 asthmatic patients (aged 16-70 years) including 15 treated with prednisolone at 5-10 mg/day (group 1,n=9), and at 15-30 mg/day (group 2,n=5). Index of stimulation (IS) of DNA repair was determined as the ratio of UV-induced to spontaneous UDS values. The comparative group consisted of 29 OCS-naive patients with similar severity. The control group included 15 healthy subjects. Results: The intensity of spontaneous UDS in lymphocytes of asthmatic patients was found to be significantly (p 0.05) the rates of both spontaneous and UV-induced UDS. However, the IS values in patients of group 1 appeared to be significantly (p Conclusions: We concluded that prednisolone in doses used does not cause any significant alterations of DNA repair synthesis in lymphocytes of patients examined. The significantly higher IS values in the group 1 of patients may be (partly) attributed to the anti-inflammatory effect.